Developing countries are characterized by low per capita real income, high population growth rate, high rates of unemployment, dependence on primary sector, dependence on exports of a primary commodity, and underutilization of natural resources. This is a broad categorization. Exploring each one of these will dig out various causes that are becoming a hindrance for the developing countries. One such hindrance is the unavailability of sufficient quantity of water in rural and urban areas of the country due to over-exploitation of natural resources.
The issue of high scarcity of water is a global issue now and those countries whose primary revenue sector depends upon the proper distribution of uninterrupted water supply get standstill when their natural water sources dry out.
Rainwater harvesting is the only solution for almost every country in the world. The only difference lies in the potential for the rainwater harvesting and the area-specific methods. Every rainwater harvesting system has a basic formation containing catchment surface, water transportation medium, filtration system and then, the storage system. The only difference is how developing countries are moving in the direction of preserving rainwater.
- Uganda
Based on reports of United Nations Development Assistance Framework for Uganda 2010-2014, almost 780 million people are deficient in accessing improved drinking water sources.
Although Uganda has relatively high annual precipitation in most of its regions, the absence of proper rainwater harvesting systems (RWH) is letting this precious natural water goes down the waste drain.
Due to high demand of clean drinking water, various government and donor organizations are now investing in effective RWH systems. With the efforts, residents and companies are taking up the installation of ferrocement tanks or the mass-produced plastic tanks on the potential RWH location. Schemes like microfinance and cost-sharing grants are stimulating the uptake of such technology.
Apart from promoting rainwater harvesting at offices, schools, hospitals, and households, other technologies aka subsurface dams, ponds and floodwater buffering are also taken up. Certain pilot technologies are under implementation such as sand dams. Since flooding is a prevalent situation in many regions of Uganda, the robust technologies are being developed to tap this abundance water.
- Mali
Mali is one of the hottest countries in the world with thermal equator crossing through it. Many places in Mali have relatively high rainfall between 500 and 1300 mm but the monsoon lives for a short period of time, resulting in a hot climate and drought like situations.
The Government of Mali has defined rainwater harvesting programme for the period 2012-2016. Some parts of the country are practicing traditional methods of rainwater harvesting such as catching the water in big rocks to store it for the later use. Since the year 2010, the development of Rainwater Harvesting Capacity Center (RHCC) in Mali is taken on to harness great potential of rainwater. It was set up to provide all the relevant references needed regarding rainwater harvesting such as documentation, spreading awareness, sharing new rainwater harvesting techniques and testing new approaches. Under their supervision, two sub-catchments, one in Koulikoro and other in Sikasso have been established in partnership with RAIN (a foundation established in 2002 for rainwater harvesting programme) to provide water for domestic, gardening, agriculture and regeneration of nature. Rainwater harvesting is done from the rooftops, sand dams, planting basins or Zai and micro-basins.
- Brazil
The “One Million Rainwater Harvesting Programme” (P1MC) was launched by civil society groups in the north-east of Brazil, semi-arid region, characterized by severe lack of water and droughts that contribute to underdevelopment of the region. This programme aims to construct one million rainwater harvesting systems for decentralized access to drinking water to one million families, or about five million people in total. The programme is carried out by Articulação do Semi-Árido (ASA), a forum of about 750 NGOs.
Based on their investigation of a household’s total annual water consumption and rainwater yield capacity, two RWH systems were proposed: a treated and a potable indirectly pumped system. The treated RWH system which meant to be used for toilet flushing, dishwashing, clothes washing and sink washing, is capable of conserving 222.65m3 /yr of potable water. The potable RWH system, applied to the existing plumbing, supplies potable rainwater into a pre-existing water tank for all uses. This system is said to conserve 456.25m3 /yr of mains water. You can read more details about these techniques here.
- China
China’s Gansu province needed extensive rainwater harvest solutions.
It is the driest province of China with the annual precipitation of about 300 mm, but a potential evaporation amounting to 1500-2000 mm.
The “121” Rainwater Catchment Project was implemented by the Gansu Provincial Government in the year 1995/96 to support farmers. The project included:
- the building of one rainwater collection field,
- two water storage tanks
- and a piece of land to grow cash crops.
By the year 2000, the Gansu Province had 2,183,000 rainwater tanks with a total capacity of 73.1 million m3 to supply drinking water to 1.97 million people and irrigating 2,36,400 HA of land. At present, seventeen other provinces of China have rainwater utilization systems having a total of 5.6 million tanks with a total capacity of 1.8 billion m3 which supplies drinking water to approximately 15 million people and irrigates 1.2 million ha of land.
- Thailand
Thailand has abundant annual rainfall ranging from 102 cm in the Northeast to over 380 cm in the peninsula.
The people in rural areas of Thailand uses two water sources – rainwater from the jars & tanks and shallow groundwater from tube wells.
Ferrocement jars of over 10 million m3 are used to store rainwater and serve as appropriate catchment system. A jar having a capacity of 2000 litres can hold sufficient rainwater which would last up to six months in a six-person household. Almost every individual house uses rainwater harvesting jars of capacities ranging from 100 to 3000 litres. These jars are equipped with lid, faucet and a drain.
Chaitanya Products – Providing RWH solutions in India
Every developing country needs a support of government and non-government agencies for providing aid in rainwater harvesting systems. Along with financial support, there is a need for modern quality RWH products.
Chaitanya products are playing their role in the development of India as a nation with an abundance of drinking and irrigational water. The company’s rainwater harvesting services provide a primary source for accessing the potential of an area for RWH activities. With most modern filtration systems for rainwater harvesting products, the clients are having more enhanced results in borewell recharge and harvesting rainwater.
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